Tropical paper looks after the care of neighbors

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Wasps provide vital support to their extended families by watching children at nearby nests, according to a new study by a team of biologists from the universities of Bristol, Exeter and UCL published today [15 February] into Ecology Nature and evolution.

The findings show that animals should often try to help more distant relatives unless the closest relationship is less necessary.

Dr Peter Kennedy, lead author and researcher at Marie Curie in the School of Biological Sciences at the University of Bristol, said: “These wasps can be wealthy family members handing over their second cousins. There is so much more you can do to help your immediate family, you can turn your attention to the extended family. “

By closely monitoring twenty thousand baby wasps and their caregivers on colonies around the Panama Canal, the research team was able to determine the usefulness of workers on colonies of various sizes. They showed that workers are becoming less useful due to the rising number of colony members, due to too much help.

Andy Radford, Professor of Behavioral Ecology, also from Bristol and co-author, explained: “By helping distant relatives who need it – those who live next door with less carers – employees can donate more copies of their genes in full. . We believe that similar principles of reducing productivity may explain paradoxical-like actions of altruism in many other social animals. “

Dr Kennedy said: “The fact that these paper wasps in Central and South America help in other colonies is very strange when you consider that most wasps, ants and bees are good hostile to outsiders. To solve this uncertain behavior, we combined mathematical modeling with our detailed field observations. “

Dr Kennedy continued: “We ended up being severely choked. But it was worth it, because our findings show that workers’ wasps can be redundant at home. very few larvae but many other workers will be almost useless: is the best thing to do to look at the larvae of other relatives. ”

Since Darwin, biologists have been trying to understand how ‘altruism’ develops in animals. At first glance, unhealthy actions to help others do not seem to allow individuals to pass on their genes.

Dr Radford said: “In 1964, the legendary biologist WD Hamilton described the high-level rule of animal altruism. Help your family greatly because they share many of your genes. Copies of your genes wins in the population. “

But the tropical paper wasps researched by the baffled Hamilton team returned in 1964. In Brazil, it was surprising to notice that Polistes wasps were leaving the family close to their home nests and flying on go to help the less closely connected neighbors.

Work by Seirian co-author ‘@WaspWoman’ Sumner, Professor of Behavioral Ecology at University College London, showed that more than half of the staff in the Panamanian population helped on several nests. Wasps usually attack people from the outside, so this childcare suggested that something unusual was going on.

Dr Sumner explained: “Wasps offer amazing windows into the evolution of instability. There is so much going on in a wasp’s nest: power struggle, self-sacrifice, groups fighting the against the living … If we want to understand how societies evolve, we should take a deeper look at wasps. ”

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This fieldwork was supported by the National Geographical Society and the Smithsonian Tropical Research Institute in Panama.

Paper

‘Diminishing returns altruists to help extended family’ by P. Kennedy, S. Sumner ?, P. Botha, NJ Welton, AD Higginson and AN Radford in Ecology Nature and evolution